Indian Patents. 231565:AN IMPROVED PROCESS FOR REMOVAL OF CHROMIUM FROM WASTE WATER USING WASTE BIOMASS OF RHIZOPUS ARRHIZUS

Title of Invention	AN IMPROVED PROCESS FOR REMOVAL OF CHROMIUM FROM WASTE WATER USING WASTE BIOMASS OF RHIZOPUS ARRHIZUS
Abstract	The present invention deals with an improved process for removal of chromium from waste water using waste biomass of Rhizopus arrhizus. , by treating the fungal waste with chromium containing solution under constant stirring at 20-40 degree C for 15-240 min followed by removal of the fungal waste from the solution to obtain desired water free from chromium.

Full Text	This invention relates to an improved process for removal of chromimum from waste water' using waste biomass of R.arrhizus. Rapid development in metallurgical and other metal related industrial sector is causing environmental concern in world wide due to the toxic role of various metal ions in different biological systems. Several industries like paint, pigment, leather tanning, electroplating, glass, ceramics, photography and textiles extensively use chromium and its compounds. These industrial effluents/waste waters contain the chromium metal in much higher concentrations than biota required quantities. Chromium is one of the essential microelement and generally helps in maintenance of enzymatic reactions of glucose metabolism, amino acid and nucleic acid synthesis in variety of biological systems. However, ingestion of chromium beyond optimal level known to cause various toxic effects- in all living beings. Chromium being a transition metal it can exist in various oxidation states starting from metallic form to ionic form and in natural waters and wastewaters, this metal generally exist in two ionic states; hexavalent chromium and trivalent chromium. Hexavalent chromium is more toxic, easily soluble, highly oxidative in nature and easily mobile then its counter part, trivalent form. In industrial effluents, the concentration of chromium ranges from 150 - 200 mg/l. The use of chromium contaminated water has been found to cause malfunctioning of stomach (epigastric pain, nausia, vomiting, irritation) and allergy to skin and respiratory track etc in human beings (Verma N and Rahul R, 1964; J Indus Pollut Control, 12; 55). In view of the above, the recovery of the metal ions from metal bearing wastewater is receiving greater attention day by day. Hereto a variety of wastewater treatment processes have been developed for effective removal of metal ions. The conventional treatment technologies includes precipitation, coagulation, ion-exchange, ultrafiltration, electrodialysis, reverse osmosis and chemisorption etc. These processes posses several drawbacks such as., A) These metal removal technologies become less effective specially when metal concentration in waste waters is in the range of 1-100 mg/l. B) Utilization of such conventional treatment techniques require continuous input of chemicals. C) They require high capital cost and manpower and D) These metal removal methodologies generates a secondary effluent, which warrants further treatment. Thus, the chemical removal of chromium metal from wastewater; is uneconomical. Microorganisms also contributed significantly in effluent treatment studies vide metal removal through biosorption. Most of the biosorption studies reported in the literature have been carried out with livingjnicrobial biomass which found to possess certain inherent disadvantages like the extreme conditions of industrial effluents are not always conducive to the growth and maintenance of an active microbial population. Moreover, viable microbes require addition of nutrients which known to enhance BOD and COD in the effluents (Lu Y and Wilkins E, 1996; J. Haz. Materials, 49; 165). This lead to utilization of non-Jiving biomass as biosorbents, which is growth independent, not subjected to toxicity limitations and does not require nutrient supply. This dead biomass can work as ion-exchanger and biosorption can be performed at wide range of operational conditions (Kuyucak N and Volesky B, 1988; Biotechnol. Lett. 10; 137). Moreover native biomass utilization in industrial or technical operations create problems in reactors by clogging and blocking the flow lines. In addition, separation of biomass and treated water is difficult and expensive owing to small size of microbe (Lu Y and Wilkins E, 1996; J. Haz. Materials, 49; 165). Very few reports are available on the microbe-metal interaction. Uptake of uranium, cobalt and cesium in Citrobactor sp. and Rhodococcus sp. was dependent on the production of phosphatase enzyme (Macaskie L E, Blackmore J D and Empson R M, 1988; FEMS Microbiol Lett, 55; 157). A directly proportional corelation between phosphatase activity and cadmium uptake in bacteria was observed (Hambling S G, Macaskie L E and Dean A C R, 1987; J. Gen. Microbiol, 133; 2743). Involvement of transport systems in metal uptake and accumulation by bacteria is noticed (Tomioka N, Uchiyama H and Yagi, 1994; Appl. Environ. Microbiol, 60; 2227). Several metabolic independent and metabolic dependent metal removal processes from solutions were noticed with various microbial species (Prakasham R and Ramakrishna S V, 1998; J. Sci. Ind. Res. 57; 258). However there is no report of metal removal utilizing industrial fungal waste as an absorbent.The presc-nt invention of chromium removal, by using industrial waste material containing fungal biomass, is an easy, effective, economic and ecofriendly technique. In addition, it also helps in fine-tuning of effluent/waste water treatment. The main object of the present invention is to provide an improved process for the removal of chromium from waste water using waste biomass of R-arrhizus. Another object of the present incvention is to provide the conversion of the bound chromium in effluent waters as free radicals. Yet another object of the present invention is use of industrial fungal waste material as adsorbent and subsequent removal of chromium ions by binding between chromium and complexion sites of biomass. Accordingly the present invention provides an improved process for removal of chromium from waste water using waste biomass of Rhizopus arrhizus , wherein the said process comprising the steps of: a) collecting of industrial fungal waste followed by washing with water; b) incubating the fungal waste obtained from step (a) at about 90 degree C to dry the said waste; c) blending the dried fungal waste obtained from step (b) to obtain the particles of fungal waste; d) treating the fungal waste obtained from step (c) with chromium containing solution under constant stirring at 20-40 degree C for 15-240 min; e) removing the fungal waste from the solution obtained from step (d) to obtain desired water free from chromium. In an embodiment of the present invention, the discarded waste material, Rhizopus arrizus, from enzyme producing industry is collected, washed twice with water in the laboratory and the excess water was removed by blotting with filter paper. This fungal biomass is then dried at 90°C for overnight in an oven. In another embodiment of the present invention, 100 - 250 mg/l chromium solution is prepared by dissolving the required quantity of potassium dichromate equivalent to chromium solution present in waste water. In yet another embodiment of the present invention, one percent of powdered fungal biomass is introduced in the chromium solution and stirred at 100 rpm to provide contact between chromium ions and the binding sites of the said biomass for 15 - 240 minutes. In another embodiment the pH of chromium solution is adjusted between 2-5 and biomass content used in a range of 0.5 -3%. In yet another embodiment of the present invention the adsorption is » carried out under stirring condition between 20-40 C in still another embodiment of the present invention, the fungal bicmass is separated from the bulk liquid by conventional filtration, or by cloth filtration. The present invention is described with reference to the following examples which are explained by way of illustration only and should not therefore be construed to limit the scope of the present invention. Example 1 Take 250 ml of 100 mg/l chromium containing liquid in 500 ml of conical flask and adjust the pH of the solution to 2.0 using 1N hydrochloric acid using the pH meter. To this added 2.5 g of powdered fungal biomass. Mix the contents of the flask and incubate at room temperature at 100 rpm in a rotary shaker. After 60 minutes of incubation the contents of the flask are subjected to filtration using whatman filter paper. Then the presence of chromium ion in the filtrate is analyzed using diphenyl carbazide as coupling agent. The purple violet colour intensity is measured by using UV spectrophotometer at 540 nm. The optical density is coOrelated with standard chromium curve and calculated the metal ion concentration in the filtrate. The analysis of filtrate in triplicate samples is given below in table -1. Table 1: Chromium presence before and after treatment of metal solution by Rhizopus arrhizus biomass (Table Removed) Example 2: One liter of 150 mg/l chromium containing solution is taken and the pH of the solution is adjusted to pH 2 using 1N hydrochloric acid with the help of pH meter. To this 10 g of Rhizopus arrhizus biomass is added and mixed thoroughly. This solution is incubated at 100 rpm at room temperature in a rotary shaker for 60 minutes. The contents are then subjected to filtration to remove the fungal biosorbent from bulk liquid. The residual chromium concentration in the filtrate is determined by coupling with diphenyl carbazide solution. The purple-violet colour intensity is measured using spectrophotometer at 540 nm and estimated the chromium concentration in the filtrate. The analysis of the filtrate, in triplicate, is given in Table 2. Table 2: Chromium presence before and after treatment of metal solution by Rhizopus (Table Removed) Example 3: In a conical flask 100 ml of 250 mg/l chromium bearing solution is taken and the solution pH is adjusted to 2 using pH meter with 1N hydrochloric acid. One gram of powdered Rhizopus arrhizus biomass is mixed with above solution and incubated at room temperature, at 100 rpm in a rotary shaker. After 60 minutes, fungal biomass is separated from the bulk liquid. The residual chromium concentration in the filtrate is coupled with diphenyl carbazide solution. Trie purple-violet colour is measured in the spectrophotometer at 540 nm. The optical density is co-related with chromium standard and estimated the chromium presence after treatment. The analysis of filtrate for chromium is given in Table 3. Table 3: Chromium presence before and after treatment of metal solution by Rhizopus arrhizus.fei (Table Removed) Example 4: Synthetic tannery effluent* was prepared by adding (in g/l) sodium bicarbonate -2; glucose -5 (as BOD, COD); sodium chloride -10 (as total solids dissolved solids); sodium sulfate -2.5 (as suspended solids); sodium sulphide - 0.1 and potassium chromate - 0.294 (as 100 ppm chromate). The pH of this synthetic tannery effluent was adjusted to 2 using pH meter with 1N hydrochloric acid. One gram of the powder Rhizopus arrhizus biomass is mixed with 100 ml of the above tannery effluent and incubated at room temperature at 100 rpm in rotary shaker. After one hour of incubation, the filtrate was collected and chromium concentration in the filtrate was estimated using diphenyl carbazide solution. The purple violet colour is measured in the spectrophotometer at 540 nm and using standard graph the chromium concentration was determined. The analysis of the filtrate for chromium is given in the table 4, Table 4: Chromium presence before and after treatment of synthetic tannery effluent by Rhizopus arrhizus. biomass. (Table Removed) * Tennary effluent was prepared according to: Third International Conference Appropriate management technologies for developing countries. NEERI, Nagpur, Feb. 25-26, 1999. The main advantages of the present invention: 1. The present invention of chromium removal is effective and efficient method and chromium removal can be achieved up to 99%. 2. The present invention of chromium removal does not produce any secondary effluent. 3. The present invention of chromium removal is cost effective process 4. The present invention of chromium removal is based on utilization of biodegradable adsorbent and does not require continuous input of chemicals. 5. The present invention of chromium removal can be used for the treatment of waste waters with metal concentration in the range of 1-100 mg/l. 6. The present invention of chromium removal can be efficiently used for the fine tuning of the chromium containing waste waters. We claim: 1. An improved process for removal of chromium from waste water using waste biomass of Rhizopus arrhizus , wherein the said process comprising the steps of: a) collecting of industrial fungal waste followed by washing with water; b) incubating the fungal waste obtained from step (a) at about 90 degree C to dry the said waste; c) blending the dried fungal waste obtained from step (b) to obtain the particles of fungal waste; d) treating the fungal waste obtained from step (c) with chromium containing solution under constant stirring at 20-40 degree C for 15-240 min; e) removing the fungal waste from the solution obtained from step (d) to obtain desired water free from chromium. 2. An improved process as claimed in claiml, wherein the fungal particle size ranges between 100-150µm. 3. An improved process as claimed in claim 1, wherein the fungal waste used is in the range of 0.5-3.0%. 4. An improved process as claimed in claiml, wherein the fungal waste is removed either by filter process or by cloth filtration. 5. An improved process for removal of chromium from waste water using* waste biomass of Rhizopus arrhizus substantially as herein described with reference to the examples.

Full Text

This invention relates to an improved process for removal of chromimum from waste water' using waste biomass of R.arrhizus.
Rapid development in metallurgical and other metal related industrial sector is causing environmental concern in world wide due to the toxic role of various metal ions in different biological systems. Several industries like paint, pigment, leather tanning, electroplating, glass, ceramics, photography and textiles extensively use chromium and its compounds. These industrial effluents/waste waters contain the chromium metal in much higher concentrations than biota required quantities.
Chromium is one of the essential microelement and generally helps in maintenance of enzymatic reactions of glucose metabolism, amino acid and nucleic acid synthesis in variety of biological systems. However, ingestion of chromium beyond optimal level known to cause various toxic effects- in all living beings. Chromium being a transition metal it can exist in various oxidation states starting from metallic form to ionic form and in natural waters and wastewaters, this metal generally exist in two ionic states; hexavalent chromium and trivalent chromium. Hexavalent chromium is more toxic, easily soluble, highly oxidative in nature and easily mobile then its counter part, trivalent form. In industrial effluents, the concentration of chromium ranges from 150 - 200 mg/l. The use of chromium contaminated water has been found to cause malfunctioning of stomach (epigastric pain, nausia, vomiting, irritation) and allergy to skin and respiratory track etc in human beings (Verma N and Rahul R, 1964; J Indus Pollut Control, 12; 55).

In view of the above, the recovery of the metal ions from metal bearing wastewater is receiving greater attention day by day. Hereto a variety of wastewater treatment processes have been developed for effective removal of metal ions. The conventional treatment technologies includes precipitation, coagulation, ion-exchange, ultrafiltration, electrodialysis, reverse osmosis and chemisorption etc. These processes posses several drawbacks such as., A) These metal removal technologies become less effective specially when metal concentration in waste waters is in the range of 1-100 mg/l. B) Utilization of such conventional treatment techniques require continuous input of chemicals. C) They require high capital cost and manpower and D) These metal removal methodologies generates a secondary effluent, which warrants further treatment.
Thus, the chemical removal of chromium metal from wastewater; is uneconomical.
Microorganisms also contributed significantly in effluent treatment studies vide metal removal through biosorption. Most of the biosorption studies reported in the literature have been carried out with livingjnicrobial biomass which found to possess certain inherent disadvantages like the
extreme conditions of industrial effluents are not always conducive to the growth and maintenance of an active microbial population. Moreover, viable microbes require addition of nutrients which known to enhance BOD and COD in the effluents (Lu Y and Wilkins E, 1996; J. Haz. Materials, 49; 165). This lead to utilization of non-Jiving biomass as biosorbents, which is growth independent, not subjected to toxicity limitations and does not require nutrient

supply. This dead biomass can work as ion-exchanger and biosorption can be performed at wide range of operational conditions (Kuyucak N and Volesky B, 1988; Biotechnol. Lett. 10; 137). Moreover native biomass utilization in industrial or technical operations create problems in reactors by clogging and blocking the flow lines. In addition, separation of biomass and treated water is difficult and expensive owing to small size of microbe (Lu Y and Wilkins E, 1996; J. Haz. Materials, 49; 165). Very few reports are available on the microbe-metal interaction. Uptake of uranium, cobalt and cesium in Citrobactor sp. and Rhodococcus sp. was dependent on the production of phosphatase enzyme (Macaskie L E, Blackmore J D and Empson R M, 1988; FEMS Microbiol Lett, 55; 157). A directly proportional corelation between phosphatase activity and cadmium uptake in bacteria was observed (Hambling S G, Macaskie L E and Dean A C R, 1987; J. Gen. Microbiol, 133; 2743). Involvement of transport systems in metal uptake and accumulation by bacteria is noticed (Tomioka N, Uchiyama H and Yagi, 1994; Appl. Environ. Microbiol, 60; 2227). Several metabolic independent and metabolic dependent metal removal processes from solutions were noticed with various microbial species (Prakasham R and Ramakrishna S V, 1998; J. Sci. Ind. Res. 57; 258).
However there is no report of metal removal utilizing industrial fungal waste as an absorbent.The presc-nt invention of chromium removal, by using industrial waste material containing fungal biomass, is an easy, effective, economic and ecofriendly technique. In addition, it also helps in fine-tuning of effluent/waste water treatment.

The main object of the present invention is to provide an improved process for the removal of chromium from waste water using waste biomass of R-arrhizus.
Another object of the present incvention is to provide the conversion of the bound chromium in effluent waters as free radicals.
Yet another object of the present invention is use of industrial fungal waste material as adsorbent and subsequent removal of chromium ions by binding between chromium and complexion sites of biomass.
Accordingly the present invention provides an improved process for removal of chromium from waste water using waste biomass of Rhizopus arrhizus , wherein the said process comprising the steps of:
a) collecting of industrial fungal waste followed by washing with water;
b) incubating the fungal waste obtained from step (a) at about 90 degree C to dry the
said waste;
c) blending the dried fungal waste obtained from step (b) to obtain the particles of
fungal waste;
d) treating the fungal waste obtained from step (c) with chromium containing
solution under constant stirring at 20-40 degree C for 15-240 min;
e) removing the fungal waste from the solution obtained from step (d) to obtain
desired water free from chromium.
In an embodiment of the present invention, the discarded waste material, Rhizopus arrizus, from enzyme producing industry is collected, washed twice with water in the laboratory and the excess water was removed by blotting with filter paper. This fungal biomass is then dried at 90°C for overnight in an oven.

In another embodiment of the present invention, 100 - 250 mg/l chromium solution is prepared by dissolving the required quantity of potassium dichromate equivalent to chromium solution present in waste water.
In yet another embodiment of the present invention, one percent of powdered fungal biomass is introduced in the chromium solution and stirred at 100 rpm to provide contact between chromium ions and the binding sites of the said biomass for 15 - 240 minutes.
In another embodiment the pH of chromium solution is adjusted between 2-5 and biomass content used in a range of 0.5 -3%.
In yet another embodiment of the present invention the adsorption is
» carried out under stirring condition between 20-40 C
in still another embodiment of the present invention, the fungal bicmass is separated from the bulk liquid by conventional filtration, or by cloth filtration.
The present invention is described with reference to the following examples which are explained by way of illustration only and should not therefore be construed to limit the scope of the present invention.
Example 1
Take 250 ml of 100 mg/l chromium containing liquid in 500 ml of conical flask and adjust the pH of the solution to 2.0 using 1N hydrochloric acid using the pH meter. To this added 2.5 g of powdered fungal biomass. Mix the contents of the flask and incubate at room temperature at 100 rpm in

a rotary shaker. After 60 minutes of incubation the contents of the flask are subjected to filtration using whatman filter paper. Then the presence of chromium ion in the filtrate is analyzed using diphenyl carbazide as coupling agent. The purple violet colour intensity is measured by using UV spectrophotometer at 540 nm. The optical density is coOrelated with standard chromium curve and calculated the metal ion concentration in the filtrate. The analysis of filtrate in triplicate samples is given below in table -1.
Table 1: Chromium presence before and after treatment of metal solution by Rhizopus arrhizus biomass

(Table Removed)

Example 2:
One liter of 150 mg/l chromium containing solution is taken and the pH of the solution is adjusted to pH 2 using 1N hydrochloric acid with the help of pH meter. To this 10 g of Rhizopus arrhizus biomass is added and mixed thoroughly. This solution is incubated at 100 rpm at room temperature in a rotary shaker for 60 minutes. The contents are then subjected to filtration to remove the fungal biosorbent from bulk liquid. The residual chromium concentration in the filtrate is determined by coupling with diphenyl carbazide solution. The purple-violet colour intensity is measured using spectrophotometer at 540 nm and estimated the chromium concentration in the filtrate. The analysis of the filtrate, in triplicate, is given in Table 2.

Table 2: Chromium presence before and after treatment of metal solution by Rhizopus
(Table Removed)
Example 3:
In a conical flask 100 ml of 250 mg/l chromium bearing solution is
taken and the solution pH is adjusted to 2 using pH meter with 1N hydrochloric acid. One gram of powdered Rhizopus arrhizus biomass is mixed with above solution and incubated at room temperature, at 100 rpm in a rotary shaker. After 60 minutes, fungal biomass is separated from the bulk liquid. The residual chromium concentration in the filtrate is coupled with diphenyl carbazide solution. Trie purple-violet colour is measured in the spectrophotometer at 540 nm. The optical density is co-related with chromium standard and estimated the chromium presence after treatment. The analysis of filtrate for chromium is given in Table 3.
Table 3: Chromium presence before and after treatment of metal solution by Rhizopus arrhizus.fei
(Table Removed)
Example 4:
Synthetic tannery effluent* was prepared by adding (in g/l) sodium
bicarbonate -2; glucose -5 (as BOD, COD); sodium chloride -10 (as total solids dissolved solids); sodium sulfate -2.5 (as suspended solids); sodium sulphide - 0.1 and potassium chromate - 0.294 (as 100 ppm chromate). The pH of this synthetic tannery effluent was adjusted to 2 using pH meter with 1N hydrochloric acid. One gram of the powder Rhizopus arrhizus biomass is mixed with 100 ml of the above tannery effluent and incubated at room temperature at 100 rpm in rotary shaker. After one hour of incubation, the filtrate was collected and chromium concentration in the filtrate was estimated using diphenyl carbazide solution. The purple violet colour is measured in the spectrophotometer at 540 nm and using standard graph the chromium concentration was determined. The analysis of the filtrate for chromium is given in the table 4,
Table 4: Chromium presence before and after treatment of synthetic tannery effluent by Rhizopus arrhizus. biomass.
(Table Removed)
* Tennary effluent was prepared according to: Third International Conference Appropriate management technologies for developing countries. NEERI, Nagpur, Feb. 25-26, 1999.
The main advantages of the present invention:
1. The present invention of chromium removal is effective and efficient
method and chromium removal can be achieved up to 99%.
2. The present invention of chromium removal does not produce any
secondary effluent.
3. The present invention of chromium removal is cost effective process
4. The present invention of chromium removal is based on utilization of
biodegradable adsorbent and does not require continuous input of
chemicals.
5. The present invention of chromium removal can be used for the treatment
of waste waters with metal concentration in the range of 1-100 mg/l.
6. The present invention of chromium removal can be efficiently used for the
fine tuning of the chromium containing waste waters.

We claim:
1. An improved process for removal of chromium from waste water using waste
biomass of Rhizopus arrhizus , wherein the said process comprising the steps of:
a) collecting of industrial fungal waste followed by washing with water;
b) incubating the fungal waste obtained from step (a) at about 90 degree C to dry the
said waste;
c) blending the dried fungal waste obtained from step (b) to obtain the particles of
fungal waste;
d) treating the fungal waste obtained from step (c) with chromium containing
solution under constant stirring at 20-40 degree C for 15-240 min;
e) removing the fungal waste from the solution obtained from step (d) to obtain
desired water free from chromium.

2. An improved process as claimed in claiml, wherein the fungal particle size ranges
between 100-150µm.
3. An improved process as claimed in claim 1, wherein the fungal waste used is in
the range of 0.5-3.0%.
4. An improved process as claimed in claiml, wherein the fungal waste is removed
either by filter process or by cloth filtration.
5. An improved process for removal of chromium from waste water using* waste
biomass of Rhizopus arrhizus substantially as herein described with reference to
the examples.

Documents:

29-del-2000-abstract.pdf

29-del-2000-claims.pdf

29-del-2000-correspondence-others.pdf

29-del-2000-correspondence-po.pdf

29-del-2000-description (complete).pdf

29-del-2000-form-1.pdf

29-del-2000-form-19.pdf

29-del-2000-form-2.pdf

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Patent Number

231565

Indian Patent Application Number

29/DEL/2000

PG Journal Number

13/2009

Publication Date

27-Mar-2009

Grant Date

06-Mar-2009

Date of Filing

18-Jan-2000

Name of Patentee

COUNCIL OF SCIENTIFIC AND INDUSTRIAL RESEARCH

Applicant Address

RAFI MARG, NEW DELHI-110001,INDIA.

Inventors:

#	Inventor's Name	Inventor's Address
1	REDDY SHETTY PRAKASHAM	THE INDIAN INSTITUTE OF CHEMICAL TECHNOLOGY, HYDERABAD-500 007, ANDHRA PRADESH,INDA
2	SONTI VENKATA RAMAKRISHANA	THE INDIAN INSTITUTE OF CHEMICAL TECHNOLOGY, HYDERABAD-500 007, ANDHRA PRADESH,INDA

PCT International Classification Number

C02F 3/34

PCT International Application Number

N/A

PCT International Filing date

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1			NA